1. Technical Field
The present invention relates to ultrasonic inspection and imaging instruments and more particularly to an ultrasonic inspection and imaging instrument which permits any person who is inexperienced in ultrasonic thickness measurement to readily focus a focusing-type ultrasonic probe (hereinafter called `probe`) on a place at a predetermined depth where an inspection is made.
2. Related Art
An ultrasonic inspection and imaging instrument as one of the ultrasonic measuring instruments (including an ultrasonic searching and imaging instrument using a focusing-type probe) is capable of displaying the interior of an object in the form of a B- and a C-scope image. An imaging instrument of this sort necessitates being fed with various measurement conditions, including the acoustic characteristics of its probe, and the wave velocity at the current temperatures of a medium of an object under examination, to set the focused probe to the interior of the object at a desired depth in order to obtain a clear image.
Heretofore, the focusing operation has been performed by observing the waveform reflected from an object under examination (A-scope image) using an oscilloscope or the like; more specifically, it comprises the steps of first setting a measurement depth, a detection gate width and the like by reference to a waveform to be monitored, moving up and down the focusing-type probe with respect to the object under examination so that a target reflection echo is maximized (positioning the depth (in the Z-direction)), and adjusting the focus of the probe to the depth desired.
Another example of the ultrasonic inspection and imaging instrument is such that, provided that measurement conditions, including acoustic characteristic values such as the wave velocity of an object under examination, the underwater focal length of a probe, a measurement depth and a detection gate width, are fed to its image processor (control unit), the image processor operates on data to focus the probe automatically onto the measurement depth desired based on the result computed.
However, an operator responsible for operating such an instrument is required to have an exhaustive knowledge as to electronic measurement, including ultrasonic measuring techniques, the acoustic characteristics of an object under examination and the operation of an oscilloscope. In other words, operators other than those specializing in this field of measurement often meet difficulties in operating an ultrasonic inspection and imaging instrument of this sort.
Incidentally, various ultrasonic inspection and imaging instruments for non-destructive inspection are now in use. This signifies the fact that those other than measuring engineers are expected to operate not only an ultrasonic inspection and imaging instrument of this kind but also a newly contrived portable one. As a result, those unfamiliar with ultrasonic thickness measurement may increasingly have a chance to handle and utilize such an instrument. It is true in a general sense that the development of an easy-to-use ultrasonic inspection and imaging instrument has been craved.
The ultrasonic inspection and imaging instrument is normally equipped with a microprocessor and an image processor having memories so that various kinds of data on varieties of operations can be preset. It is consequently possible to preset data concerning certain operations in order to simplify a series of them. Notwithstanding, there practically arise difficulties in presetting data to simplify the series of operations, as it depends on the object under examination how to solve the focusing problems. Consequently, engineers who have a thorough understanding of the acoustic characteristics and material quality of an object under examination and the like are relied upon to perform such focusing operations. In so doing, the engineer involved has to display and observe the interior ultrasonic conditions of the object under examination using the A-, C-scope image or the like as occasion demands to take measurement conditions and the like into consideration. The situation above has made it difficult to solve the foregoing problems.